Celebrity Champions on “Who Wants to Be a Millionaire” starting September 20.

Watch Alzheimer’s Association Celebrity Champions test their knowledge on “Who Wants to Be a Millionaire,” starting Sept 20. In recognition of World Alzheimer’s Day, Sept. 21, contestants including Peter Gallagher (“The O.C.,” "Covert Affairs"), Victor Garber (“Alias”), Jean Smart (“24,” “Samantha Who?”) Evan Lysacek (Gold medalist, Olympic figure skating), Mario Cantone (“Sex and the City”), Melora Hardin (“The Office”) and Melissa Rivers ("Joan & Melissa: Joan Knows Best?") will test their knowledge and earn cash to benefit the care, support and research efforts of the Association.

Cheer on all of these celebrity Champions by watching “Who Want to Be a Millionaire” starting September 20-24. For show times, check your local listings.